Vibratory screen



Patented Dec. 3,135

2,062,529 VIBRATORY somrsn Jean Sahut, Raismes, France Application March 20, 1935, Serial No. 12,062 In FranceMarch 31, 1934 2 Claims. (oi. 209-326) The present invention relates to vibratory screens of the type including means, such for instance as shafts carrying unbalanced masses,for imparting a vibratory movement to different points of the .screen proper.

The object of the present invention is to provide a screening apparatus of this type which is.

better adapted to meet the requirements of actual practice than apparatus of the same kind used up to the present time and, in particular, capable of preventing, or at least greatly reducing, clog-- ging of the screen meshes.

The essential feature of the present invention consists in imparting different vibratory movements to the respective ends of the elastically supported screen through shafts carrying unbalanced masses and acting on different portions of said screen. Said shafts are caused to revolve at different speeds and preferably the shaft acting on the end of the screen onto which the matter tobe screened is fed is caused to revolve at a higher speed than the shaft acting on the oppositeend of the screen.

Other features of the present invention will result from the following detailed description of a specific embodiment thereof.

A preferred embodiment of the present invention will be hereinafter described with reference to the accompanying drawing, given merely by Way of example, and in which:

Fig. 1 is an elevational view of a screen apparatus according to the present invertion;

Fig. 2 is a corresponding plan view;

Fig. 3 is a sectional view'on the line 3-3 of Fig. 2.

In this embodiment of the invention, A is a rigid frame on which one or severalscreening surfaces B are stretched longitudinally. The vibrating means include two parallel shafts D and E, rotating, either in the same direction or in onposite directions, inside tubes F forming cross According to the present invention, the vibratory movements imparted to the respective ends of the screen are different, the transmission means above referred to so devised that the speeds of revolution of shafts D and E are different, the speed of revolution of shaft D (which corresponds to the end of the screen onto which the matter to be sifted is poured) being preferably higher than the speed of revolution of shaft E. 5

By way of example, I have found that very satisfactory results were obtained by rotating shaft D at a rate of 2350 revolutions per minute and shaft E at a rate of 1900 revolutions per minute.

The whole is suspended, in an inclined posi- 10 tion, at several points, through elasticdevices, or it is supported by these devices. In the example shown by the drawing, collars K surround the outer casings of the ball bearings of the shafts. Each collar K has, integral therewith,.a tail whichis guided by a threaded rod M between two piles of rubber rings or the like L, slipped over said rod and the compression of which is ad'- justable by means of nuts screwed on said rods.

The remainder of the screen is of any suitable '2 conventional or other design.

While I have, in the above description, disclosed what I deem to be a practical and efficient embodiment of the invention, it should be well understood that I do not wish to be limited there- 25 to as there might be changes made in the arrangement, disposition and form of the parts Without departing from the principle of the present invention as comprehended within the scope of the appended claims.

What I claim is;

1. A screening apparatus which comprises, in combination, an inclined rigid frame, a screen stretched between the upper and lower ends of said frame, two horizontal shafts journalled ;in 35 said frame, one near the upper end thereof and the othernear the lower end of said frame, unbalanced masses carried by said shafts respectively, means for driving said shafts with different respective speeds of revolution, and-elastic means for suspending said frame.

,a -A screening apparatus which comprises, in combination, an inclined rigid frame, a screen stretched between the upper and lower ends of said frame, two horizontal shafts journalled in 45 said frame, one near the upper end thereof and the other near the lower end thereof, unbalanced masses carried by said shafts, respectively, means for driving said shafts in such manner that the speed of revolution of the first one is higher than the speed of revolution of the other, and elastic means for suspending said frame.

JEAN SAHUT. 

